Mechanism for shifting points of tramway-lines.



no; 714,398. I

- Patented Nov. 25, I902, G. 1-8088. MECHANISM FOR SHI'FTING POINTS OF TRAMWAY LINES.

{Application filed July 11, 1902.)

No Model.)

Nrrno STATES GEORGE DOW ROSS, OF GLASGOW, SCOTLAND.

MECHANISM FOR SHIFTING POINTS OF TRAMWAY-UNES.

SPECIFICATION forming part of Letters Patent No. 714,398, dated November 25, 1902..

' Application filed July 11,1902. Serial in. 115.205. wombat;

To all whom it mag concern."

Be it known that I, Gnonon Dow Ross, en-

ginecr, of 12 Regent Park Terrace, Stratlr,

I along? y A drawback in connection with the shifting mechanisms heretofore proposed is that no provision has been made for preventing the shifting apparatus breaking should a stone or such like find its way into the rail and jam the point so as to prevent its shift ing. This is a very serious drawback, as it is impossible to prevent stones orother bstructions getting now and then into the groove of the rail. The present invention has for its object to obviate the above drawback by providing a simple appliance or attachment which can be let the apparatus work without shifting the point.

In order that the invention may be prop e ly understood, I havehereunto appended explanatory drawings, which show, in-.

Figure 1, a complete point-shifting device in section; Fig. 2, one form ofmy present iuvention; Figs. 3 and 4, other forms of the i11 vention,

In the arrangement shown at Figs. 1 and 2 the point-shifting table a and rocking arm b, operated from the car and which may both be the same as in my prior patent aforesaid,'are

connected, by means of a link c, to a rocking lever d, which is jointed to the connectingrod e, which latter is attached to thetongue fof the switch-point g in the groove of the train-rail h. The connecting-rod e is made in two parts e e, the one part epassing through an eye in a lugj on the other part On the part c there are two strong springs in l, which are coiled. around the part and bear at their inner ends against the lug aforesaid and at their outer ends against nuts m n on the part. The nuts m moan be screwed up to regulate the tension of the springs.

The mechanism may be inclosed in a box 0, provided with removable coversp q and sunk into place in the roadway and between the train-rails.

In the arrangement Fig. 3 the part e of the connectingrod works through a hole in a stirruppiece r, jointed to the lever d. The springs Z bear against the bridge 8 of the stirrup.

In the arrangement Fig, 4 the two parts e L of the connecting-rod are simply joined togather by a stiff spring 171..

In all cases the springs 70 Z are made of such strength that when the apparatus is working properly they will be stiff enough to shift the point 9 without yielding to any appreciable extent; but when the point jams they will yield to such an extent as to allow the parts a b a (Z i to work without shifting the point.

Then a single spring is used, as at Fig. 4, it is made sufiiciently stiff to ordinarily shift the point without compressing or expanding to any appreciable extent. When the point is jammed, it will yield su-liiciently to allow the car to operate the table a without operating the point.

Having now fully described my invention, what I claim, and desire to secure by Letters Patent, is-,

A device of the type set forth, comprising a rocking table adapted to be operated from the car, an arm connected to the table, a link connected at its one end to said arm, a rocking lover having its lower end connected to the other end of said link, a connecting-rod named and of the second-maimed part and said so formed in two parts, one of the parts having nuts. I a connection with the switch-point the other Signed at; Glasgow, Scotland, this 19th day of the parts being pivotally connected at its of June, 1902. one end to the upper end of said rocking, leverend havingibs other end slidably mounted on said firebmemed part, nuts suitably spaced on said first-named part, and springs on said first-named part engaging said last- GEORGE Dow ROSS.

Witnesses WILLIAM GALL, W. D. 'FITZPATRICK; 

